Transcript GEM-based detector projects at GSI

GEM-based detector projects at GSI
(in the framework of JointGEM)
PANDA Central- and Forward-Tracker
(GEM-TPC & GEM-DISCs)
Bernd Voss
Helmholtzzentrum für Schwerionenforschung GmbH (GSI)
The Panda Experiment
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
2
The Future:
PANDA at FAIR
Facility for Antiproton and Ion Research, Darmstadt, Germany
p production
target
PANDA
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
3
Proto ANtiproton DArmstadt Experiment
Overview
p Target
Superconducting
solenoid (2T) +
iron return yoke
p
Silicon
Microvertex
Detector
Central Tracker
• Straw tubes
• GEM-TPC
B. Voss
GEM-Projects@GSI
GEM-Tracker
planar GEM-DISCs
3rd
Meeting@HIP
July 15th 2010
4
PANDA Central Tracker
Requirements & Layout

Full solid angle coverage

Secondary vertex resolution σrφ~150μm, σz~1mm

Momentum resolution
δp/p~(2)%

Minimal material budget
X/X0~(2)%

Particle Identification
δE/E~(7)%

Operation in 2T magnetic field
 Time Projection Chamber (TPC*)
MPGD: high granularity, fast signal,
good multi-track resolution

Continuous operation at high rate
(space charge, event mixing)
 …with GEM amplification
reduced ExB effect,
suppressed ion feedback
*D.R. Nygren et al., Phys. Today 31, 46 (1978)
B. Voss
GEM-Projects@GSI
3rd

2 half cylinders L=150cm R=15/42cm

Drift field 400 V/cm

Ne/CO2 (90/10), max. drift time 55µs

Multi-GEM stack

Pad Size ∼2x2mm2, 100.000 ch
Meeting@HIP
July 15th 2010
5
Planar GEM-Tracker
Basic assumptions

1
0 1
2
3

Figure of Merit:
Relative momentum
resolution dp/p (p,θ,z,r)

particle momentum p

scattering angle θ

vertex coordinates z, r
Basis assumptions:

GEM-TPC short version
(1,5 m  1,2 m)

4 GEM-DISCs (GEM0..3)

Equal sizes GEM1=GEM2
!
Maximize shape-conformity
Target spectrometer@PANDA ‘V833’
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
6
Planar GEM-Tracker
Angular range
Active area
Requirements
~ 2..21 (..30)°
0,6..1,7 m2
Material budget
(active area)
< 0.5% X0 (per GEM station)
Position resolution
< 0.1 mm
Counting rate capability
< 40 (..140) kHz / (cm2 s)
Resistance
against aging effects
Stable operation at design luminosity for 10y lifetime
Track efficiency degradation < 2% / layer
(per GEM station)
10 mm
Positional
Double track
to be checked against expected pile-up event rate
resolution
Angular
5°
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
7
The ‚real‘ world
Hardware
Test TPC
‘large‘ TPC Prototype
…
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
10
Planar GEM-DISCs
Detector assembly
Possible cabling hooks:
central bar & circumference
Window
GEM stack
Drift
electrode
B. Voss
GEM-Projects@GSI
Cooling
Pad Plane
Support
Support
&
&
LV- Distribution
MediaDistribution
3rd
Meeting@HIP
Front-End
Electronic
Shielding Cover
&
Read-out Plane
July 15th 2010
11
‘large’ TPC Prototype
Detector Assembly
Resistor strips /gas line / HV-line
Field
Cages
In preparation
Assembly done
Several
hundred pieces
Cathode
B. Voss
Electronic
Flange
GEM
Flange
Media
Flange
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
12
Pad Size & Geometry
Residual cluster width (x) (cm)
PadPlane Design
with diffusion
w/o diffusion
Pad radius (cm)
 1.5 mm outer pad radius
10.000 (Prototype) up to 100.000 (Final) channels
105 / 300 mm ‘active’ diameters
1,5
mm radius, hexagonal pads
0,2
mm gap
10296
active Pads in total
42
sectors
cylindrical symmetry
300
pins/connector
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
13
QA & inspection

Large area 1180 x 800 x 500 mm machinery
(upgraded later on)

High precision σ(i) ≈ 5µm

High resolution digital microscope 54 MPix

B. Voss
GEM-Projects@GSI
3rd

Various magnifications x10..1000

2D and 3D Pictures & Measurements

Various Lighting- & filter options
,multi-purpose
Meeting@HIP
July 15th 2010
14
Pad-Plane
… quality checks on geometry


Device under test

‘Hexagon’ Pad-Plane

QA looking for
shape distortions
Design (42 bores)


Circle radius:
175,00 mm
Ellipse
rx:
174,99 mm
ry:
174,02 mm

Excentricity:
0,99985

Deviations: Δrmax: 0,11 mm

Δrmin : 0,01 mm
Fit


 Design goals accomplished
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
15
PadPlane assembly
‘…glued into the frame’

Centre part
on GND potential
Dead Pads due to
Support ring
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
16
GEM-Assembly
Foil mounting
GEM-flange assembly
Single-flap contact
B. Voss
GEM-Projects@GSI
3rd
5 / 50
105 / 300
8
iris like
70 /140
µm Cu on Kapton
mm ‘active’ diameters
sectors
pattern
µm double conical CERN
‘standard’ arrangement
18 Mio holes in total
Inner & outer GFK support rings
leakage current < 10 nA/sector@650V
Hole geometry checked at 5 points
Optical transmission (36 ± 3)% @2x3mm
check once per sector
Meeting@HIP
July 15th 2010
17
‘…stacked on the flange’
GEM assembly
Central GEM-HV supply

HV-protection
 HV-stability tested, Design goals accomplished
cover
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
18
Tools & Tests
Universal Test-Box

Universal for all assemblies & -combinations
Single-GEM, GEM-stack, PP, GS+PP, GS+PP+FEE…


8h
0,5nA
B. Voss
GEM-Projects@GSI
3rd
Features

Stable & Highly accessible

‚Radiation transparent’ (x-ray / rad. sources)
entrance& exit-windows

EMV shielding, Gas compartment,
1:1 connections feed trough
Use case: GEM-foil test
10 foils, leakage current per sector:

Immediate at 650V <10nA (CERN)

Immediate at 550V (3.11.8) nA, max. 6.3 nA

after 8h
at 600V <0,5 nA
Meeting@HIP
July 15th 2010
19
Tools & Tests
GEM / Pad Plane Test stand

B. Voss
GEM-Projects@GSI
3rd
Tasks / Tests:

Verify Pad Plane functionality

Test GEM amplification uniformity

Commission Front-End Electronics
Meeting@HIP
July 15th 2010
20
GEM Test chamber
… some results
Gain with voltage
Pulse height in Ar/CO2 (70/30)
Pulse Height
Cu X-ray
8.0-8.9keV
Current
Gain uniformity
55Fe
5.9keV
1
2
3
6
5
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
4
July 15th 2010
21
Full test assembly
‘…waiting for HV-Test’
Mounting the Test-Cathode
Looking for gas leaks

B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
22
… work still ongoing
Field Cage
Rohazell®
Al on Kapton® shield
Kapton®
reinforcement
80..240µm
Gas channels
Staggered strip line
Cu on Kapton® / FR4
Resistor- (6x2)
strips
(≈900)
split chains,
paired, 1..5 W
10%
w(1mm) g(0.5mm) 20..100 µm thick
backside shifted by ½
Linear Heater
System
GEM-Projects@GSI
High Voltage
29 kV
Drift field
400 V/cm
Heat dissipation 5 W
(not visible)
Outer & Inner
FieldCage
o=300mm i=105mm L=702mm
B. Voss
8% 7%
3rd
Meeting@HIP
3mm
July 15th 2010
23
Tools
Field-Cage Mould
Vacuum
grooves
Inner structures
(w/o heater)
paneling
before
milling
Temperature
pickup
B. Voss
ready
to use
Metapor®
panels
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
24
Field-Cage Fabrication…first hand laminated sample


First hand-laminated samples

(wet-in-wet, stacking as for Cathode end-cap)
 Al / Kapton
22,5 µm
 Rohazell
2 mm
 Kapton
2x80 µm
 Kapton / Al
22,5 µm
 Without strip-line, resistors,
gas channels…

First results look promising
but still room for improvements

B. Voss
GEM-Projects@GSI
3rd


Heater & Control unit
optimized material budget
with prepreg / melting-foil lamination
Work done on flat & curved samples:
stitching, part mounting, gas distribution,
test of mech. stability, HV-stability etc.
Many recent improvements in details
(processes, solutions)
Next steps:
 Production & test of ‘real’ parts
Meeting@HIP
July 15th 2010
25
Field-Cage Fabrication …hand laminated cathode

First hand-laminated sample
(wet-in-wet, stacking as for field cage)
 Al / Kapton
22,5 µm
 Rohazell
2 mm
 Kapton
2x80 µm
 Kapton / Al
22,5 µm
 Not cut out yet…

First results look promising (flatness, stiffness)
but still room for improvements (weight)
 Problematic because of space resrictions:


B. Voss
GEM-Projects@GSI
3rd
HV-line & joint ground-braking solution missing
Isolation at edges & rims (Corona discharges)
Meeting@HIP
July 15th 2010
26
…sample resistor chains
The voltage divider(s)
SMD 0603/0805 Resistor chain
(1 out of 4..6)

Strip 966
Cu (2x25µm incl. Au-plating & Coverlay )
on Kapton (≈50µm)
Gap
0.5 mm
Strip
1 mm
(Cathode)
Gas
holes
Strip 1
(3.GEM)

Good shape conformity
 Manual soldering takes 162h / field cage
Gas
holes  Done sucessfully:
 Test on flat samples
stitching, mech. stability, gas penetration,
HV-Stability, part mounting, handling etc.

inside
outside
B. Voss
GEM-Projects@GSI
3rd
Next steps:
 Production & test of full-size samples
 Semi-automatic part mounting
Meeting@HIP
July 15th 2010
27
Tools
Thin-foil Stitcher

B. Voss
GEM-Projects@GSI
Setup design:

flexible to join various foil- thicknesses & widths with 2 mm ‘tape’

Stable & high-precision (10µm)

Vacuum chucks keep foils in position
and sufficiently flat

Controlled & regulated heating system
3rd
Meeting@HIP
July 15th 2010
28
Tools
Solder-paste
deposition
Electronic Components
Part Mounting
Reflow
Soldering

Integrated into the (x,y,z) facility

Advantages:


Fast prototyping

High shape flexibility

Large specimen sizes
Limitations:


 Nearly complete but if not ready in time…
B. Voss
GEM-Projects@GSI
3rd
2 component types per run
Main applications

GEM-TPC Field Cage
(> 20000 SMD resistors)

PadPlanes
hand-mounting is still an option
Meeting@HIP
July 15th 2010
29
MediaFlange assembly
‘…needs a backplane’

‘Cover’ plate
ready too
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
30
Read-Out End-Cap
Test Assembly
Dummy
Cathode
GEMFlange
Media
Flange
Read-Out
Electronic
Low
Voltage
Cooling
Overall things seem to fit
B. Voss
GEM-Projects@GSI
3rd
some details to be worked at
Meeting@HIP
July 15th 2010
31
T2K ‘AFTER’
…used for the prototype tests
• AMS CMOS 0.35 µm technology
• 76 channels / chip, 4 chips/card
• Charge-sensitive preamp
• Shaper, t programmable
• analog sampling at 10 – 50 MHz
• analog ring buffer 511 cells
• external trigger  MUX at 20 MHz
• expected noise: 500 e- at 10 pF
• power consumption < 0.6 W/chip
• Electronics delivered for 10kch
• Fighting with small problems
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
32
A use case… The CB-ELSA Experiment
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
33
ELectron Stretcher Accelerator (ELSA)
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
34
Crystal-Barrel@ELSA (CB-ELSA)
• e- beam: 0.5-3.5 GeV, ~ nA, polarized
• tagged photon beam, polarized
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
35
GEM-TPC in CB-ELSA
• Polarized target: butanol 2x2x2 cm3
• Crystal Barrel Detector
1230 CsI crystals, 6°x6°
• Inner detector: part. discr.
cylinder of 513 SciFi
• Forward plug: 12°-30°
90 CsI crystals with PMT: trigger
• Forward detector (MiniTAPS)
216 BaF2, 1°-12°
• CO2 gas Cherenkov detector
to suppress e.m. background
no tracking, no timing
see HK 57.9 Alexander Winnebeck
TPC
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
36
Beam Test at CB-ELSA
…work ongoing
Trigger
scintillators
e-
GEM-TPC
GEM

Beam: 500 MeV e-

Track definition by external telescope

Alignment using photogrammetry + tracks
Silicon
microstrip
4xSCI, 2xGEM (10x10cm2, 2Dstrip ) + 4xSi planes
Test-TPC: 3xGEM 10x10cm2, 7.7cm drift, ∼1500 hex.pads, T2K readout
 Objectives: systematic studies of gain, uniformity, gas parameters, space charge,
ion feedback, cosmic tracks, (spatial) resolutions


Has been brought to and set up at COMPASS (still in preparation)
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
37
GEM-TPC in FOPI @ GSI
Barrel
CDC
GEM TPC
RPC
PLAWA
L
y
z
Helitron
x
‘Spider’
Support

Integration well advanced with respect to
supplies, mechanics, DAQ

Temperature gradient (h,v) ≈ (3.4,1.5) °C
measured in-place (preliminary)

B. Voss
‘Bucket’
GEM-TPC
possible counter actions?
cooling, measure & correct
GEM-Projects@GSI
Restricted volume
3rd
Meeting@HIP
CDC outer support
July 15th 2010
39
Prototype plans


Measurement program at FOPI

Light ion beam, 2 AGeV/c, e.g. Li, 104-107 ions per spill (4s or 8s)

Polyethylene target

Gas: Ne/CO2 (90/10)

Shaping time 200 ns, sampling rate 20 MHz

Gain scan

Different intensities (beam, target)
Goals

Spatial- & momentum resolution

dE/dx capabilities

Rate effects
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
40
Roadmap for GEM-TPC@FOPI*) …a tough endeavor
10.10.
End of changing set up for next experiment
24.09.
Start of test run (shift by one week in discussion)
06.09.
Deadline detector implementation
23.08.
Start cosmics calibration-measurements
01.08.
Start lab tests
31.07.
Finishing assembly of full detector system
30.06.
End of production of FieldCage
…?
Ongoing: GEM-Assembly tests, treatment of sensor signals
Pending: StripLine Foil delivery
To be done: set up HV-stability test to 45kV
Shift by one week in discussion
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
41
Summarizing…
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
42
Summary & Outlook


Detector Construction & Assembly

Well advanced: GEM-, Media- & Electronic-Flange

Assembly of these components for lab.-tests in April

Field Cage is the ‘last challenge’; goal: ready in June

Electronic issues understood, full scale readout to be set up until April
Commissioning & testing

Well prepared: single-component tests, cosmics test stand,
in-beam test stand at CB-ELSA

Mechanical & Slow Control & DAQ-Integration into FOPI & CB-ELSA prepared
/ in progress, supply lines installed

Reconstruction with PANDA Root set up

Proof-of-principle tests in August-October 2010 at FOPI

First results by end of 2010, PANDA-TDR by middle of 2011

Serious work on a GEM-Disc Prototype started recently
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
43
The GEM-TPC & GEM-Tracker Collaboration
Heinz Angerer2, Reinhard Beck3, Martin Berger5, Felix Böhmer2,
K. -T. Brinkmann3, Paul Bühler4, Michael Carnegie4, Sverre Dørheim2,
Laura Fabbietti5, Chr. Funke3, F. Cusanno5, Jörg Hehner1, Andreas Heinz1,
Markus Henske1, Christian Höppner2, David Kaiser3, Bernhard Ketzer2,
Volker Kleipa1, Igor Konorov2, Jochen Kunkel1, Michael Lang3, Johann Marton4,
Sebastian Neubert2, Stephan Paul2, André Remers1, Holger Risch1, Alexander
Schmah5, Christian Schmidt1, Roman Schmitz3, Sandra Schwab1, Daniel Soyk1,
Ken Suzuki4, Ulrike Thoma3, Eduard Traut1, Maxence Vandenbroucke2,
Bernd Voss1, Jan Voss1, Dieter Walter3, Joachim Weinert1, Eberhard Widmann4,
Alexander Winnebeck3, H. -G. Zaunick3, Xiaodong Zhang2, Johann Zmeskal4
1
2
3
4
5
GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany
Technische Universität München, Physik Department, Garching, Germany
Helmholtz-Institut für Strahlen- und Kernphysik, Bonn, Germany
Stefan-Meyer-Institut für subatomare Physik, Vienna, Austria
Technische Universität München, Excellence Cluster “Universe”, Garching, Germany
Backup slides
High Energy Storage Ring (HESR)
High intensity mode
• L  2 1032 cm -2s -1
• p/p  104(stoch. cooling)
High resolution mode
• L  1031 cm-2s-1
• p/p  105(e- cooling)
Antiproton storage ring
• p injection at 3.7 GeV/c
• Synchrotron: 1.5 – 15 GeV/c
• Internal targets: H, nuclei
PANDA
from CR
B. Voss
GEM-Projects@GSI
3rd
from SIS18
Meeting@HIP
July 15th 2010
46
Physics at PANDA

QCD bound states

Charmonium

Gluonic exitations above 2 GeV/c2

Heavy-light systems

Strange and charmed baryons

Hadron properties in nuclear medium

Double hypernuclei production an spectroscopy

Nucleon structure


Generalized distribution amplitudes

Time-like electromagnetic form factors

Transverse spin distribution in nucleons
Electroweak physics
B. Voss
GEM-Projects@GSI
3rd
Meeting@HIP
July 15th 2010
47